Biomedical subjects

M P Campbell

Publications and source records attributed to M P Campbell.

4 recordsLinked to original sources

PubMed1999

The impact of diaphragm management on prolonged ventilator support after thoracoabdominal aortic repair.

PURPOSE: The relationship of the division of the diaphragm during thoracoabdominal aortic repair to prolonged ventilator support has not been studied. The purpose of this study was (1) to determine whether preservation of diaphragm integrity has a significant effect on postoperative ventilator duration and (2) to elucidate other pulmonary risk factors related to thoracoabdominal aortic surgery and to study the relationship of these factors to the intact diaphragm technique. METHODS: Between February 1991 and January 1997, we repaired 397 descending and thoracoabdominal aortic aneurysms. Descending thoracic aneurysms were not included in the study because their repair does not include the diaphragm. A total of 256 patients participated in this study. The diaphragm was divided in 150 patients and left intact in 106 patients. Examined as potential risk factors were patient demographics, history and physical findings, aneurysm extent, urgency of the procedure, acute dissection, cross-clamp time, homologous and autologous blood product consumption, and adjunctive operative techniques. FEV1 also was considered in the 197 patients for whom preoperative spirometry was available. Prolonged mechanical ventilation was defined as ventilator support for >72 hours. Data were analyzed by univariate contingency table and multiple logistic regression methods. RESULTS: Increasing age (odds ratio [OR], 1.02/y; P <.02), current smoking (OR, 2.6; P <.0008), total cross-clamp time (OR, 1.0/min; P <.008), units packed red blood cells transfused (OR, 1.06/unit; P <.008), and division of the diaphragm (OR, 2.03; P <.02) were significant, independent predictors of prolonged ventilation. Sixty-seven percent of patients (71 of 106) whose diaphragms were preserved were extubated in <72 hours compared with 52% of patients (78 of 150) who underwent diaphragm division (OR, 0.53; P <.02). CONCLUSION: Independently of well known pulmonary risk factors, an intact diaphragm during thoracoabdominal aortic repair results in a higher probability of early ventilator weaning.

Adolescent↗

PubMed1998

Thoracic and thoracoabdominal aortic aneurysm repair using cardiopulmonary bypass, profound hypothermia, and circulatory arrest via left side of the chest incision.

PURPOSE: Although some authors advocate hypothermic circulatory arrest for spinal cord protection in descending thoracic and thoracoabdominal repair, this method has been associated with high morbidity and mortality rates in other studies. The safety and effectiveness of this surgical adjunct were evaluated. METHODS: Between February 1991 and April 1997, 409 patients underwent thoracic or thoracoabdominal aortic repair. Because of an inability to gain proximal aortic control because of anatomic or technical difficulty, hypothermic circulatory arrest was used in 21 patients (4.9%). Thirteen patients were men, 8 were women, and the median age was 57 (range, 21 to 81 years). Four patients (19%) had Marfan's syndrome, and 1 had aortitis. Seven patients (33%) had aortic dissection (4 chronic type A, 2 chronic type B, 1 acute B), and 1 had aortic laceration. All but 6 patients had hypertension. Fifteen patients (73%) were operated on for repair of the distal arch and descending thoracic aorta, 4 (19%) for repair of the distal arch and thoracoabdominal aorta, and 2 for repair of either the thoracoabdominal or descending thoracic aorta alone. Surgery for 9 patients (43%) also included bypass grafts to the subclavian or innominate arteries. Six operations (29%) were urgent. RESULTS: The overall 30-day mortality rate was 29% (6 of 21 patients). Among urgent patients, the mortality rate was 50% (3 of 6 patients) versus 20% (3 of 15) for elective patients. Of the remaining 15 patients, renal failure occurred in 1 (7%) and heart failure in 2 (13%). Ten patients (67%) had pulmonary complications. Encephalopathy occurred in 5 patients (33%) and stroke in 2 (13%), and spinal cord neurologic deficit developed in 2 (13%). The median recovery was 28 days (range, 10 to 157 days). CONCLUSION: Hypothermic circulatory arrest did not reduce the incidence of deaths and morbidity to a rate comparable with our conventional methods. We recommend the judicious application of this method in rare instances when proximal control is not feasible or catastrophic intraoperative bleeding leave the surgeon with no other option.

Adult↗

PubMed1998

Spinal cord protection in descending thoracic and thoracoabdominal aortic aneurysm repair.

During aneurysm repair of the descending thoracic or thoracoabdominal aorta, the likelihood of neurological complications increases greatly after only 30 minutes of spinal cord ischemia. However, the manifestation of paraplegia or paraparesis relates not only to aortic cross-clamping time, but to multiple factors that may include aortic dissection, previous aortic surgery, advanced age, preoperative renal insufficiency, rupture, and most significantly, aneurysm extent. At greatest risk is the patient with type II thoracoabdominal aortic aneurysm. For this patient the simple cross-clamp technique, which uses no protective surgical adjuncts, heightens the threat of neurological deficit. With the surgical adjuncts of cerebrospinal fluid drainage and distal aortic perfusion, the probability of neurological deficit is appreciably lowered.

Aortic Aneurysm, Abdominal↗

PubMed1997

Cerebral spinal fluid drainage and distal aortic perfusion decrease the incidence of neurological deficit: the results of 343 descending and thoracoabdominal aortic aneurysm repairs.

OBJECTIVE: We reviewed our experience of 343 descending and thoracoabdominal aortic aneurysm repairs to determine the impact of the adjuncts distal aortic perfusion and cerebral spinal fluid drainage on neurological deficit and death. MATERIALS AND METHODS: Between January 1991 and March 1996, 104 (30%) patients were operated for thoracoabdominal aortic aneurysm type I, 118 (34%) for type II, 68 (20%) for type III or type IV, and 53 (15%) for descending thoracic type. Before September 1992, simple cross-clamp was used for 94 (27%) patients. After September 1992, adjuncts were used for 186 (54%) patients. RESULTS: Overall neurological deficit was 33/343 (10%). Neurological deficit for simple cross-clamp patients compared to adjunct patients was 15/94 (16%) vs. 12/186 (7%) (O.R. 0.36, p < 0.01). For types I and II the incidence was 11/52 (21%) vs. 12/141 (9%) (O.R. 0.35, p < 0.02) and for type II, nine out of 22 (41%) vs. 11/85 (13%) (O.R. 0.21, p < 0.003). Overall 30-day mortality was 43/343 (13%), including patients presenting with rupture. Excluding these patients, overall 30-day mortality was 33/322 (10%). CONCLUSION: Cerebral spinal fluid drainage and distal aortic perfusion decreased the incidence of neurological deficit and were particularly effective for patients at highest risk with type II thoracoabdominal aortic aneurysm.

Adolescent↗